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By L. A. Stinnett

An investigation of hazardous surface openings of abandoned and inactive underground mines in the Black Hills area of South Dakota has revealed: (1) tracing legal ownership of mineral claims via county courthouses is confusing, complex, and oftentimes misleading, (2 ) in general, the selected mine openings in this investigation are to be considered relatively high in risks and hazard potential which poses a threat to the general public, (3) mine closure procedures and designs can generally be categorically implemented depending on the overall situation of the particular mine opening with subsequent unit costs' estimates, (4) few preventive state or federal legal measures exist to date concerning mine closures, and (5) liability damages relating to mine opening accidents usually involve expensive and complex common law cases.

Jan 1, 1979

By J. H. Holden, C. C. Shale, G. R. Strimbeck, W. S. Bowie

Electrical characteristics are presented for air in a 2 - inch pipe - type electrostatic precipitator operating under dynamic conditions at temperatures of 600 ° to 1,500 ° F and pressures of 0 to 80 psig using a negative discharge electrode . Results of this one - geometry study show that current - voltage relationships are a function of air pressure and temperature and indicate that precipitators can be used at any temperature through about 1,350 ° F over the full range of pressure . Corona starting voltage and sparkover voltage vary directly with pressure and inversely with temperature . At temperatures above 1,350 ° F use of precipitators may be limited to operations at pressures somewhat above atmospheric pressure . Theoretical derivations are presented that relate the effect of gas density on corona starting voltage and the effect of ion mobility on corona current . Deviation from the theory is noted at high current levels . Theoretical discussion is presented to explain the apparent electrical limitations for use of precipitators at high temperature , low gas density , and high corona currents , conditions at which calculated ionic velocities are extremely high . Experimental results are interpreted in terms of the theory presented . 1,500 ° F thermal ionization does not appear to be a critical factor .

Jan 1, 1963

By Richard I. Barnhisel

At the Sinclair Study Site it was found that the deeper the soil the greater the yield of corn, soybeans, wheat, alfalfa, and timothy. Yields at this location were generally lower than those at the Alston Surface Mine. At Alston the non-prime land treatments generally produced greater yields for all crops than did the prime farmland treatments, however, the intermediate soil thickness, 20 cm topsoil over 40 cm of subsoil, gave the best yields, provided it's subsoil had been limed. From a chemical point of view, acidic spoils do not need to be buried by 120 cm or 4 feet of soil, provided adequate lime is applied to these spoils as a barrier prior to placement of good quality topsoil and only forage crops are to be grown. The burial depth must be increased to as much as 75 cm when grain crops such as corn or soybeans are to be grown. This response to burial depth appears to be related to water storage needed by the crop and not due to toxic effects of the spoils. A conventional farm tractor-mounted subsoiler increased yields of soybeans and corn the first one or two years, but the effect was diminished with time. Subsoiling did not produce significant increases for alfalfa or wheat. However, ripping with a bulldozer produced significant yield responses, especially for corn and soybeans, that have lasted for at least three years. The ripping effectively reduced the bulk density at least within the zones through which the ripper had passed. Liming the upper 20 cm of subsoil significantly increased yields of alfalfa, corn, and soybeans. There also appeared to be an interaction between this lime treatment and soil depth. Yields of some grain and forage crops may be high enough to meet target levels for bond release for prime farmland. Based on the present study, one should not expect corn yields to be high enough to meet bond release. This statement should not be considered final since the experiment is not complete.

Jan 1, 1983

By A. L. Service

Idaho has nearly 6 billion tons of potential sources of phosphorite, 10 to 31 percent P2O5' above and within 100 feet below entry level, the largest potential of any State in the United States. In 1963 Idaho ranked third after Florida and Tennessee in total mine and marketable production of phosphate rock; Montana ranked fourth. This report describes phosphate deposits, mines, and prospects in 10 districts covering most of the Idaho phosphate field. All mine production of phosphate rock in Idaho comes from surface mines and is processed to phosphate fertilizers, phosphoric acid, and elemental phosphorus. Producing districts are Fort Hall (Gay mine), Trail Creek (Conda and Ballard mines), and Crow Creek (Georgetown Canyon mine). FMC Corp. and J. R. Simplot Co. at Pocatello have the largest elemental phosphorus and fertilizer production facilities, respectively, in the State, followed by Monsanto Co. and El Paso Natural Gas Products Co. (formerly Central Farmers Fertilizer Co.). The only other major phosphate processing plant in the State is the phosphoric acid and phosphate fertilizer complex at Kellogg operated by the Bunker Hill Co. In 1963 a plant was constructed and put on line at Monsanto, Idaho, to recover vanadium from ferrophosphorus produced by electric furnace operations in the area. El Paso Natural Gas Products Co. completed construction of a fertilizer and phosphoric acid plant near Conda in 1965. There is a small fertilizer plant producing phosphate fertilizers for local consumption in Soda Springs.

Jan 1, 1966

By Eugene T. Sheridan

This circular presents data on individual plants of the fuel-briquet and packaged-fuel industries that responded to the Bureau of Mines annual economic survey and reported production for 1959. The companies named herein represent virtually all producers of processed fuels of mineral origin. A few small companies may not have been canvassed or failed to respond, however, as some plants operate intermittently, and the survey is voluntary. No consideration was given to size of the plant and all plants that reported commercial production were included. Specifically excluded were plants that manufactured briquets from wood charcoal. Fuel briquets and packaged fuel are manufactured solid fuels, fabricated from fine-sized mineral fuels by mixing with binders and compressing into small individual shapes. Briquets usually are produced as small, pillow-shaped pieces, 2 to 4 inches long, weighing 2 to 4 ounces. Packaged fuel consists of 3- to 4-inch cubes, 6 or 8 of which are wrapped in heavy kraft paper to form a package weighing 10 to 15 pounds. The overall size of a popular package is 10-112 x 7 x 3-1/2 inches. Briquets are durable, may be stored outdoors, and shipped and used as bulk fuel. Packaged fuel is fragile, and must be stored indoors to keep it from deteriorating. Whereas briquets are consumed in many areas as a general residential fuel, packaged fuel is more of a specialty item, used at times as a supplement to other fuels. Package fuel is burned without removing the paper and referred to as the "white-glove" fuel.

Jan 1, 1960

By A. R. T. Denues

"INTRODUCTION The orienting phases of the current investigation of cushioned blasting in the Explosives Division of the Bureau of Mines were indicated in a previous publication (5) 3/. Pertinent literature reviewed therein indicated a highly controversial field. This emphasized the need for experimental studies of many factors that affect the health and safety of miners and the efficiency of mining operations. Results of some orienting tests showed marked effects on practical hazards. Further, they emphasized the necessity and importance of the contemplated investigation. The scope and general plan of these practical inquiries into the safety of cushioned blasting were indicated.This investigation of cushioned blasting relates to the various means employed to reduce the intensity of application of energy from explosive actions in boreholes. It has been suggested (from p. 19 of reference that the divisions of this work would correspond to the salient hazards affected by cushioned blasting. These include the ignition hazard, hazards from poisonous gases, and other practical hazards in the blasting technique. The ignition hazard was resolved into two components of approximately equal weight. These include studies of effects upon (1) the incendivity of blown-out shots and upon (2) the occurrence of such shots. Experimental studies of effects on the incendivity of blown-out shots were first undertaken. Questions of the best procedure for making these evaluations have been adduced, and the interpre-tation and utilization of the results of gallery testing seemed to require detailed attention; some preliminary general considerations of such testing were therefore necessary."

Jan 1, 1943

By Árpád B. Palotás, Adel F. Sarofim, John B. Vander Sande, Lenore Rainey Christian, J. Feldermann

"Interest in the fine structure of soots and carbon blacks is motivated by a variety of possible applications. The structure provides information on the origins of the particles and on their adsorptive and reactive properties. This paper describes a method for quantification of the structure of soots and carbon blacks based on direct electron microscopic observation followed by image analysis of these materials. High-resolution transmission electron microscopy (HRTEM) provides a very detailed observation of particle structure. The differences in soot structure, because of its complexity, may not be easily quantifiable with the human eye; therefore, high-level computer software has been used to manipulate HRTEM images. This technique involves the application of fast Fourier transforms (FFT) to single particles and the measurement of characteristic parameters such as interplanar spacings and crystallite sizes from these particles. The methodology and application of this characterization technique are presented here. Results are shown for dif¬ferent samples obtained from soot and carbon black particles selected to illustrate the capabilities of the methodology. Quantitative information can be obtained on structural characteristics, e.g., interplanar spacing, circularity, orientation, elongation, and length distribution of lattice fringes, as well as on the fractional coverage of the extracted pattern. c 1996 Wiley-Liss, Inc.This paper presents a combination of techniques for recognizing and classifying different carbonaceous materials, using their structural morphology. A new method to assess and quantify the parameters which define such structures is proposed and discussed. The technique is based on the use of HRTEM (high-resolution transmission electron microscopy) and computational image analysis.It is well-known that carbonaceous materials like graphite, soots, coals, cokes, chars, etc. possess characteristic structural appearances which can vary from mostly random or amorphous to a perfectly ordered graphitic crystalline structure (Buseck and Bo-Jun, 1985; Buseck et al., 1987). The carbon structure has been variously described as turbostratic (Oberlin, 1989) or as crumpled sheets (Rouzaud et al., 1991) to indicate that parallel layering, reminiscent of graphite, is observed over dimensions of nanometers, but that these planes or crystallites show disorder over larger scales. The degree of order of such structures is strongly dependent on the thermal treatment of the material as well as on the composition of the source of the carbonaceous material. The value of the electron microscope in studying the morphology of such materials has been well-established, and abundant information is available (Ishiguro et al., 1991; Lahaye and Prado, 1978; Buseck, 1992).The use of HRTEM has brought further insight into this matter. Qualitative assessment of the structural order of such materials has been attempted over a long period of time in order to differentiate between various sources or treatments. There is, to date, no successful method available for quantifying the structural characteristics of various carbonaceous materials. This paper presents a technique which is able to recognize dif-ferent materials and to quantify the structural parameters of those materials using HRTEM and computational image analysis, including pattern recognition techniques.In the case of perfectly ordered graphitic crystals, electron diffraction is widely used for obtaining details on structure. Analysis of diffraction patterns can reveal parameters such as interplanar spacing, d002, crystallite size along the c-axis, Lc, crystal size in the plane of the layers, L., mean number of crystallites, Nc, etc.Complicated electron microscopy methods such as defocusing, tilted illumination, axial illumination, etc., often have to be used in order to characterize complex materials such as randomly oriented crystals in soots and carbons. Obtaining the right fo"

Jan 1, 1998

By M. A. Lucas

The Bureau of Mines has developed a computerized mathematical model to predict the distribution of accessory elements throughout a metallurgical process. The model can be used to determine process conditions that effect better accessory element control consistent with continued high primary metal recovery. The model presented is specific for determining the bismuth distribution in lead smelting but can be adapted to most extractive metallurgical processes. Thermodynamic, kinetic, and process parameters form the base for the model. Its logic and structure are described in detail.

Jan 1, 1983

By D. R. Tesarik

Displacement and stress changes in cemented backfill and ore pillars at the Buick Mine, near Boss, MO, were monitored by engineers from the U.S. Bureau of Mines and The Doe Run Co., St Louis, MO. A test area in this room-and-pillar mine was backfilled to provide support when remnant ore pillars were mined. Objectives of this research were to evaluate the effect of backfill on mine stability, observe backfill conditions during pillar removal, and calibrate a numeric model to be used to design other areas of the mine. Relative vertical displacements in the backfill were measured with embedment strain gauges and vertical extensometers. Other types of instruments used were earth pressure cells (to identify loading trends in the backfill), borehole extensometers (to measure relative displacement changes in the mine roof and support pillars), and biaxial stressmeters (to measure stress changes in several support pillars and abutments). Two-and three-dimensional numeric codes were used to model the study area. With information from these codes and the installed instruments, two failed pillars were identified and rock mass properties were estimated.

Jan 1, 2010

Minerals are a fundamental component of the Nation" material and economic base. Without a continuous supply of minerals to meet growing and changing needs, the basic character of our society would be very different. The importance of minerals to the United States was reemphasized by the Congress in I970 when it enacted the Mining and Minerals Policy Act, which stated that it is the continuing policy of the Federal Government in the national interest to foster and encourage private enterprise in (I) the development of economically sound and stable domestic mining, minerals, metal and mineral reclamation industries, (2) the orderly and economic development of domestic mineral resources, reserves, and reclamation of metals and minerals to help assure satisfaction of industrial, security and environmental needs, (3) mining, mineral, and metallurgical research, including the use and recycling of scrap to promote the wise and efficient use of our natural and reclaimable mineral recources, and (4) the study and development of methods for the disposal, control, and reclamation of mineral waste products, and the reclamation of mined land, so as to lessen any adverse impact of mineral extraction and processing upon the physical environment that may result from mining or mineral activities.,.

Jan 1, 1977

By Marvin W. Wilson

The Federal Bureau of Mines has conducted laboratory experiments simulating underground gasification of coal to study the feasibility and mechanism of the process and determine the chemical and physical characteristics of a coal-bed during gasification. Laboratory and small-scale field experiments also were made to investigate the properties of coal and other factors affecting the electrolinking-carbonization method of preparing a path through a coalbed before gasification. Laboratory experiments simulating underground gasification of coal: Experiments with a laboratory retort indicated that bituminous-coal deposits could be gasified in place to produce a combustible gas.

Jan 1, 1960

By G. L. Fitzpatrick

Future applications of seismic holography to "seismically transparent phase objects," such as rock inclusions, fracture zones, liquid-filled cavities, etc., will require techniques to improve the poor image contrast generally characteristic of these objects. Although conventional phase-contrast enhancement techniques could be used, these methods involve additional optical elements such as quarter-wave spatial filters. Owing to the anticipated practical difficulties of properly alining such optical devices and properly locating poorly defined image planes and filter planes, this approach is not considered to be well-suited to the case of seismic holograms and their laser reconstructions. Results similar to those achieved with spatial filters may be obtained without filters by specially processing the seismic hologram data. The new process, which is an extension of Gabor's subtraction holography, achieves an improvement in contrast by an interferometric technique. The process involves adding a ?before" hologram without an object present to a 90° phase-shifted "after" hologram with the object present. Then, the combination is reconstructed with a laser or by computer. Not only is the image contrast improved in such processed holograms, but the images are also phase-contoured. In general, the latter feature is not to be expected when conventional phase-contrast enhancement techniques are employed. The new technique is experimentally verified by examining computer-generated synthetic seismic holograms rather than by examining actual seismic field data. However, results of this study are directly applicable to real seismic data and should prove useful in future applications of seismic holography.

Jan 1, 1973

By John C. Gagliardi

The U.S. Bureau of Mines, in cooperation with Carter Mining Co., conducted vibration tests of four off-road vehicle seats. The purpose of the tests was to determine which seat provided the best vibration attenuation under laboratory conditions. Laboratory tests were constructed to simulate the mining vibration environment within the limitations of the test equipment. The acceleration test levels and corresponding response of the seats were low compared to ISO 2631's fatigue-decreased-proficiency time limits. Two of the seats employed mechanical suspensions and two seats employed air suspensions. The seats were tested using a 22,241-N (5,000-lbf) electrodynamic shaker. Mechanical suspension seats were tested with various preload-to-mass ratios (PMR's) and cushion densities. Air suspension seats were tested with various air pressure levels and seat cushion densities. Air suspension seats provided good vibration attenuation if pressurized greater than 552 kPa (80 psi). Mechanical suspension seats' attenuation performance decreased if the PMR exceeded 9.8. Seat cushions of lower density provided less vibration damping.

Jan 1, 2010

By S. H. Ash

The Pennsylvania anthracite-mining region is the only one in the world of major magnitude. As the deposits of anthracite in the United States are limited virt113.lly to Pennsylvania, the difficulties of this industry have been commonly considered a State rather than a national problem. However, there is also national interest in the conservation and wise utilization of all fuel resources and in the control of interstate waterways. The anthracite industry is confronted with the very se:;-ious :problem of accumu.lation of water in many of the mines. This problem must be solved soon if progressively higr-er mi~ing costs are to be avoided. The water proble~ cannot be solved by the operating compa,nies without State or Federal aid, or both, owing to the magnitude of the work requir~d, diversity of interests of the coal ana surfa.ce ovmerships, hazard to the whole mining community, and interests affec~ed outside the mining region. The cost of abati~ the ever-increasing_surface seepage to mine workings and of handling this seepage once it }3s occurred is beyond the economic resources of most ope~ating ma.'18.gements. The data in this paper giving the high lights of the water problem and indicating what appears to be a step in the right direction are based upon observations made during the past year that the industry desires and believes it is to the npublic interesttr to keep mine workings free of flood end surface waters.

May 1, 1941

By Dean H. Ambrose

Using three-dimensional (3-0) graphics computing to evaluate new technologies for computer-assisted mining systems illustrates how these visual techniques can redefine the way researchers look at raw scientific data. The U.S. Bureau of Mines is using 3-D graphics computing to obtain cheaply, easily, and quickly information about the operation and design of current and proposed mechanical coal and metal-nonmetal mining systems. Bureau engineers developed a graphics simulator for a continuous miner that enables a realistic test for experimental software that controls the functions of a machine. Some of the specific simulated functions of the continuous miner are machine motion, appendage motion, machine position, and machine sensors. The simulator uses data files generated in the laboratory or mine using a computer-assisted mining machine. The data file contains information from a laser-based guidance system and a data acquisition system that records all control commands given to a computer-assisted mining machine. This report documents the first phase in developing the simulator and discusses simulator requirements, features of the initial simulator, and several examples of its application. During this endeavor, Bureau engineers discovered and appreciated the simulator's potential to assist their investigations of machine controls and navigation systems.

Jan 1, 1992

By Bernadette C. Michalski

Mineral raw materials, labor, capital, and technology form the basis of industrial production. The augmentation of one or all of the elements--labor, capital, and technology--will result in industrial growth. Thus, an increase in the labor force would increase output. A similar result would be achieved by expanding capital investment and supplying labor with more equipment. Finally, industrial growth can be achieved by introducing more productive methods and techniques born of technological advancement. The Soviet Union has employed these elements in many patterns to catapult from an agricultural to an industrial economy in four decades. The early history of the Soviet Union was marked by limited capital and borrowed technology, forcing the Soviets to concentrate on an abundant labor reserve to support the industrial program. The source of this reserve was the rural population. In [1928], 80 percent of the working population was employed in agriculture. This figure dropped to 43 percent by 1956, whereas industrial employment in the same period increased from 8 to 31 percent.3/

Jan 1, 1960

By Curt D. Edgerton

This study was made to determine trends in fresh water usage by California petroleum refineries, to forecast fresh water requirements to 1975, and to evaluate water conservation practices. Statistical data used in the study were obtained largely from published sources and from records of selected companies. An adequate sampling of the State's refining capacity was obtained, and the data were extrapolated to the total California refining capacity. A breakdown of the data was then made on the basis of the following refining regions: (1) the Los Angeles Basin and Southern Coastal region, (2) the Southern San Joaquin Valley, and (3) the San Francisco Bay area. An unpublished forecast of crude oil input to refineries by a major oil company operating on the West Coast was used as a basis for predicting fresh-water usage. The 1963 fresh water intake by California petroleum refineries was 84 million gallons per day. This is expected to increase to 128 million gallons per day by 1975. The fresh-water to crude-oil ratio is increasing in all regions except the Southern San Joaquin Valley. At present, the supply of fresh water available to almost all of the State's petroleum refineries, mostly from surface sources and company-owned wells, is adequate, although shortages may develop within the foreseeable future. Present conservation methods are centered around the following four objectives: (1) minimum intake of fresh water of the lowest possible quality commensurate with sound technologic practice; (2) optimum recirculation; (3) proper treatment before discharge; and (4) substitution of air cooling for water cooling.

Jan 1, 1965

By Donald I. Bleiwas

The U.S. Bureau of Mines has evaluated the potential availability of nickel from 36 deposits or districts in 16 market-economy countries (MECs), analyzing more than 95 percent of production in those countries. This study indicates the quantity of nickel available on the basis of net production costs and total costs with a 0-pct and a 10-pct discounted cash flow rate of return (DCFROR). Costs of production are expressed in dollars per pound of recovered nickel. The study also indicates sensitivities of the cost of production to energy, labor, and other factors. The studied deposits and properties contain approximately 33 Mmt of recoverable nickel. About 26 Mmt of nickel is potentially recoverable from laterite deposits, of which 4.5 Mmt can be produced at $2.50/lb or less with a 0-pct DCFROR. Approximately 7 Mmt of nickel is potentially recoverable from sulfide deposits, of which about 6.3 Mint could be produced at $2.50/lb or less at a 0-pct DCFROR. The price of nickel averaged above $6.00/lb in 1988. Sensitivity studies performed for both laterite and sulfide deposits indicate that the total cost of producing nickel from laterites is most sensitive to increases in energy costs and that the total cost of producing nickel from sulfide deposits is most sensitive to increases in labor costs; sulfides are also affected by changes in revenues from byproducts.

Jan 1, 1991

By Richard S. Fowkes

Advanced technology, including automation and computerized information systems, is being adopted in mining at an ever-increasing rate to improve safety and productivity and to decrease overall costs. This U.S. Bureau of Mines report focuses on the human factors issues related to advanced technology. Among the significant facts discovered were the following: Experts studying tile design adoption, and implementation of new technology have stated repeatedly that human factors specialists should be involved from the early planning stages, through design and fabrication, and up to and during production, since human factors has been consistently identified as the biggest obstacle to the efficient utilization of new technology. Also, middle management is generally the greatest obstacle to the adoption of advanced technology, this technology can give rise to worker alienation, boredom, stress, job insecurity, and a sense of isolation; training most of the present work force is more cost effective than hiring new workers; workers are willing to accept new technology if they are given a voice in its implementation; the social and the technical systems should be jointly optimized; and with the intro¬duction of advanced technology, the cognitive or mental, rather than the physical, aspects of human-machine interaction must be emphasized.

Jan 1, 1994

By J. M. Kuchta

The chemical and thermal criteria used for predicting the spontaneous combustion hazard are briefly reviewed and data are presented to characterize the gas desorptions and self-heating tendencies of 29 U.S. coals. Closed vessel desorption experiments showed that CO, CO2, and CH4 are the main gases evolved and that the CO, CO/?O2 index, and 02 absorption rate increase with decreasing rank and increasing oxygen content of the coal. In this Bureau of Mines report, the effects of temperature, moisture, and other variables are discussed together with the application of the data to the complex conditions encountered in a mining environment. An important finding is that the presence of CO alone in a mine is not necessarily an indication of a self-heating reaction of the coal. Based upon experiments conducted in an adiabatic-type calorimeter, the self-heating temperatures of lignite and subbituminous coals can be as low as 30° C, whereas the bituminous coals require a temperature of about 60° C or more. The self-heating hazard is greatest when the coals are dried and exposed to a high humidity condition, apparently as a result of the "heat-of-wetting." Generally, the hazard is greatest with the western coals of the United States.

Jan 1, 1980